Peoria. Ill. (WMBD) – A large plume of dust from the Sahara Desert in Africa has been making it’s way west across the Atlantic Ocean over the past week and will start to impact part of the U.S. mainland on Wednesday. A portion of this dust plume could impact Central Illinois this weekend.
What is the Saharan Dust Layer
The Saharan Dust Layer, commonly referred to as the Saharan Air Layer (SAL) by meteorologist, develops as westerly winds blow small dust particles from the Sahara Desert off the west coast of Africa near the Cabo Verde Islands and across the Atlantic Ocean. Within the layer of dust resides a dry and very warm desert air mass that acts to suppress the development of tropical systems. In fact the SAL is generally monitored for hurricane forecasting.
It’s fairly common to have dust from the Sahara Desert blow off the African coast in June and July and make it’s way to Central and North America. By the time the dust makes it here, it typically becomes diluted resulting in a thin haze across the southern U.S. However, this particular dust plume has remained fairly dense as it traversed the Atlantic resulting in poor visibility and poor air quality across the Caribbean early this week.
Impacts to Central Illinois
Model forecasts bring some Saharan dust to Central Illinois Friday evening and keep it in place through the upcoming weekend. The dust is expected to bring hazy skies and fantastic sunsets to the region throughout the weekend as it filter’s out sunlight. The warm and dry air associated with the SAL could also impact our weekend storm chances by creating a capping inversion that could act to limit storm development if the approaching cold front stalls before it gets here.
Impacts on Health
Increased dust in the air, particularly near the surface, would create poor air quality and have an impact on those with respiratory issues. This threat is even more serious in the age of COIVID-19.
That said, it’s unclear how much of an impact the Saharan dust plume will have Central Illinois’ air quality this weekend. While most of this dust sits between 5,000 and and 15,000 feet a good portion of it has made it’s way to the surface over the Caribbean. This is likely due to high pressure aloft which pushes air towards the ground.
The center of that high pressure system will be over the Gulf Coast this weekend and is the area most likely to deal with poor air quality. Further north and closer to Central Illinois we will have stronger winds aloft and an approaching cold front which could help dilute some of the dust and keep it from pooling near the surface. If you are person who struggles with respiratory issues, continue to monitor the air quality forecast over the next few days.